This dissertation examines the responses that liberal culturalism and neo-Roman republicanism provide to the question of what position the democratic state should adopt in contexts characterized by the presence of individuals and groups who have different cultural and religious commitments to those of the majority culture and religion. Our study consists of an original and comparative theoretical reconstruction of the answers given to this question by eight dominant political theories within these two currents. Concerning liberal culturalism, this dissertation examines the answers given by the liberal theory of minority rights (Kymlicka), the perfectionist theory (Raz), the nationalist theory (Tamir) and the neutralist theory (Patten). Regarding the neo-Roman republicanism, this dissertation examines the theory of freedom and government (Pettit), the deliberative theory (Maynor), the critical theory (Laborde) and the republican patriotism (Viroli, Habermas and Laborde). This research is intended to contribute to the clarification and systematization of these theories and defend the idea that liberalism and republicanism are both philosophically compatible with the government consideration of cultural and religious diversity, in particular because of the adaptation of their fundamental principles to the contemporary pluricultural reality.